Block for sheets of abrasive material



u 1929- J. JOHNSON 1,724,651

BLOCK FOR SHEETS OF ABRASIVE MATERIAL Filed July 28 1926 ,T man. (1 Jofinso 1 Patented Aug. 13, 1929.

UNITED STATES INGMAN J. JOHNSON, OF LOS ANGELES, CALIFORNIA.

BLOCK FOR SHEETS F ABRASIVE MATERIAL.

Application filed July 28, 1926.

My invention is a block for sheets of abrasive material.

An object of my invention is a block adapted to hold sheets of abrasive material such as sand or emery paper or the like, so that same may be readily used for abrasive purposes.

Another object of my invention is to construct the block in such manner as to hold the paper so that substantially all of same may be utilized without waste and in addition to shape the block so that the paper may be readily used for different shapes of surfaces to be sanded or otherwise abraded. In

' this regard my block provides large flat surfaces, a convex surface and an angular surface having any desired angle less than 180 degrees.

Another specific object of my invention is to form the block in such manner that it may be hinged having two separate leaves and a covering material providing the hinge structure.

A further feature of my invention is in the manner of clamping the leaves of the block together, providing for different thicknesses of sand or other abrasive paper.

My invention will be more readily understood from the following description. and drawings, in which;

Figure 1 is a perspective view of my abrasive block showing the same in the clamped or operative position;

Fig. 2 is a perspective view of the block showing same in an open position for attaching the sand or abrasive paper;

Fig. 3 is a perspective detail of one of the leaves showing the section for holding the end of the abrasive paper;

Fig. 4 is a detail view showing one of the holding edges of the block shaped to form a modified angular abrading surface;

Fig. 5 is a detail similar to Fig. 4, showing a concaved curved edge.

My block! is constructed of two leaves designated by the numerals 1 and 2, each of these leaves having a flat inner surface 3 and a flat outer surface 4, a curved edge 5 and a straight'angular edge 6, this edge preferably being inclined inwardly from the outer to the inner flat surfaces. The inner surface 3 has a lengthwise rabbet 7 The block is covered with a fabric 8 or other suitable material which is preferably glued on to the rabbet, the inclined edge 6, the outer surface 4 and the curve 5 or suit- Serial No. 125,417.

ably secured thereto by tacks or the like, thus forming a longitudinal hinge 9 for the blocks. The sand or abrasive paper indicated by the numeral 10 is fitted over the edges 6 of the leaves with the ends 11 extending into the rabbets 7, this being adjusted so that when the block is closed when in the position of Fig. l the paper is tightly drawn over the outside surfaces of the block.

The blocks are provided with dowels 12 and dowel holes 13 which cooperate, and with a clamping device 14 on each end. These clamps are constructed by having a pair of pins 15 secured on one of the leaves, a plate 16 having slots 17 therein, the slots engaging over the pins and the plate being retained in position by the heads of the pins. These slots are inclined to the edge of the plate. A proect ng finger 18 engages a pin 19 on the opposite leaf of the block, this clamping plate eing provided with a finger grip 20 preferably by bending same at right angles.

From the above construction it will be seen that when the pin 19 is engaged by the finger l8 and the plate pressed lengthwise of the slots 17 that the leaves may be firmly clamped together or slightly loosened or entirely loosened to allow the leaves to open. By this construction I provide for different thicknesses of abrasive paper.

It will be noted by my construction that when the block is in the position for use as shown in Fig. 1, the surfaces 5 form a continuous concave edge 21 from end to end of the block, and that the edges 6 form a V- shaped groove 22 extending from end to end of the block. This may have any suitable angle less than 180 degrees. In Fig. 4 I illustrate the edges 6 as sloping in the reverse direction so that the edges form a projecting V-shaped edge 23 and in Fig. 5 I show'the edges 6 formed in a concave curve 24. These different shapes are merely illustrated of changes which may be made to suit different types of Work for which the block may be designed.

It is apparent by the construction of the block illustrated that the sand or other abrasive paper may be tightly clamped in the block and substantially all the surface used until worn out; that very little of the paper is wasted in the gripping structure and that the paper may be clamped sufliciently tight so that it will not slip on the surfaces of the block.

It will be noted by the construction shown particularly in Figs. 1, 2 and 3 that the inwardly inclined V-shaped groove 22 allows the sand papering of a number of difierent shapes which fit approximately in this groove, and it may thus be used for sand papering angles on material and various other projections. Moreover, the V-shaped groove 22 provides an especially firm grasp for the hand, allowing the fingers to fit therein so that they are protected from splinters and other causes of injury.

It is obvious that my invention may be changed considerably in general construction or in specific details to suit different purposes. Such changes would be within the spirit of my invention as set forth in the description, drawings and claims.

Having described my invention, what I claim is:

1. 'A block for sheets of abrasive material comprising a pair of block leaves hinged together, means on the edge of each of the leaves to frictionally engage the ends of a sheet of abrasive material, a clamping device comprising a plate having inclined slots, a finger spaced in the plate, pins secured to one of the leaves and engaging in the slots, iaind a pin on the other leaf engaging the nger.

2. A block for sheets of abrasive material comprising a pair of block leaves each having a curved edge, means hinging the leaves together at said edges, the opposite edge being formed at an angle to the sides of each leaf, each leaf having a rabbet on the inclined edge to frictionally engage the ends of a sheet of abrasive material, clamping devices on the ends of each leaf, each constructed with a plate having inclined slots and a spaced finger, pins engaging said slots ialnd a pin in the opposite leaf engaging the nger.

3. A block for sheets of abrasive material comprising a pair of block leaves having flat rial forming a hinged joint, clamping devices each comprising a plate having inclined slots and a spaced finger, pins secured to one of the leaves engaging the slots and a pin in the opposite leaf to engage the finger.

4. A block for sheets of abrasive material, said block comprising a pair of block leaves having a covering forming a hinged joint, abrasive material fitted over said blocks and over the hinged oint, the said material being caught underneath the free edges of the block leaves, the said leaves when the block is folded together forming an inwardly extending V-shaped surface with abrasive material on the free edges.

5. A block for sheets of abrasive material comprising a pair of block leaves, each having a curved edge, means hinging the leaves together at said edge, the opposite edge of the block when folded together having an inwardly inclined V-shaped edge, a sheet of abrasive material engaging the free end of each of the block leaves and passing over the upper sides, the curved edge and the V shaped edge, a pin secured on the end of one of the blocks, a plate having inclined slots slidably mounted on the other leaf, and a finger on the plate to engage the said pin.

6. A block for sheets of abrasive material comprising a pair of block leaves hinged together at one edge, means on the opposite edge of each of the leaves to engage the ends of a sheet of abrasive material, the ends of the block leaves being fiat, and a clamping device having a wedging means secured to the flat ends to clamp a pair of leaves in folded position.

7.'A block for sheets of abrasive material comprising a pair of block leaves hinged together at one edge, means on the opposite edge of each leaf to engage the ends of a sheet of abrasive material, said latter edge, when the leaves are hinged together, forming a V-shaped groove with the point of the V inward, and a clamping device having a wedging means secured to the ends of a pair of leaves to hold such leaves and abrasive material in folded position.

In testimony whereof I have signed my name to this specification.

INGMAN J. JOHNSON. 

